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port boundary condition vs. PML+port boundary condition

Posted Apr 26, 2011, 11:17 a.m. EDT RF & Microwave Engineering, Results & Visualization, Studies & Solvers Version 4.2a 5 Replies

Elif
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Hi all,

I get different results when I use port boundary condition and PML together than when I only use port boundary conditions for input and output. I've calculated transmittance and reflectance and the difference for transmittance is quite significant.

Why I have low transmission when I use PML and port together? Cannot port boundary condition prevent reflection?

I would appreciate any answers,

Thanks in advance..


5 Replies Last Post Jun 12, 2013, 5:05 p.m. EDT
Shakeeb Bin Hasan
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Posted: 1 decade ago Apr 27, 2011, 6:35 a.m. EDT
May be because your system is not strongly single mode something which port boundaries are ideally suited for. All the modes apart from the specific mode the port can absorb get (partially) back-reflected resulting in erratic results.
May be because your system is not strongly single mode something which port boundaries are ideally suited for. All the modes apart from the specific mode the port can absorb get (partially) back-reflected resulting in erratic results.
Elif
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Posted: 1 decade ago Apr 27, 2011, 7:00 a.m. EDT

May be because your system is not strongly single mode something which port boundaries are ideally suited for. All the modes apart from the specific mode the port can absorb get (partially) back-reflected resulting in erratic results.


Thank you for your answer,

I am actually simulating a broad range but in single mode range even with very dense meshes I still obtain the same behaviour.
[QUOTE] May be because your system is not strongly single mode something which port boundaries are ideally suited for. All the modes apart from the specific mode the port can absorb get (partially) back-reflected resulting in erratic results. [/QUOTE] Thank you for your answer, I am actually simulating a broad range but in single mode range even with very dense meshes I still obtain the same behaviour.
Claus
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Posted: 1 decade ago Sep 6, 2011, 10:44 a.m. EDT
To me it also sounds like you system is not strictly single mode.

I guess otherwise you made your system work combining ports and pmls. I am curious to hear how you made it work. Perhaps you could upload you mph file. I am trying to combine ports and pmls in 3d but I am getting a strange error, which means I can still run the simulations but the result is no fields. I should say my simulations are ok without pmls.
To me it also sounds like you system is not strictly single mode. I guess otherwise you made your system work combining ports and pmls. I am curious to hear how you made it work. Perhaps you could upload you mph file. I am trying to combine ports and pmls in 3d but I am getting a strange error, which means I can still run the simulations but the result is no fields. I should say my simulations are ok without pmls.
Elif
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Posted: 1 decade ago Sep 6, 2011, 2:48 p.m. EDT
Hi Claus,

In order to combine port boundaries and PML, I followed the documentation in the below link, there is also case for 3D:

www.comsol.com/showroom/documentation/model/6141/
Hi Claus, In order to combine port boundaries and PML, I followed the documentation in the below link, there is also case for 3D: http://www.comsol.com/showroom/documentation/model/6141/
Yan Guan
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Posted: 1 decade ago Jun 12, 2013, 5:05 p.m. EDT

Hi Claus,

In order to combine port boundaries and PML, I followed the documentation in the below link, there is also case for 3D:

www.comsol.com/showroom/documentation/model/6141/


Hi Elif,

I can not open the link now. Is that possible you may send me the document? I have the problem that if I use PML and port together, there is no electric field.

Thank you very much.
[QUOTE] Hi Claus, In order to combine port boundaries and PML, I followed the documentation in the below link, there is also case for 3D: http://www.comsol.com/showroom/documentation/model/6141/ [/QUOTE] Hi Elif, I can not open the link now. Is that possible you may send me the document? I have the problem that if I use PML and port together, there is no electric field. Thank you very much.

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